altcha-org/altcha · Security
Altcha Proof-of-Work obfuscation mode cryptanalytic break
- GHSA ID
- GHSA-mpmc-qchh-r9q8
- CVE ID
- CVE-2025-65849
- Severity
- medium
- Published
- Updated
- CVSS v4
- 5.5 · CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:P
Description
A cryptanalytic break in Altcha Proof-of-Work obfuscation mode version 0.8.0 and later allows for remote visitors to recover the Proof-of-Work nonce in constant time via mathematical deduction.
CWEs
- CWE-327 · Use of a Broken or Risky Cryptographic Algorithm
References
- https://nvd.nist.gov/vuln/detail/CVE-2025-65849 ↗
- https://altcha.org/docs/v2/obfuscation ↗
- https://github.com/altcha-org/altcha/blob/154f874cbcdd4e639783463130d13988a2bd1bdc/src/helpers.ts#L170-L194 ↗
- https://github.com/eternal-flame-AD/altcha-deobfs ↗
- https://github.com/advisories/GHSA-mpmc-qchh-r9q8 ↗